Reducing embodied carbon in UK construction | One Click LCA

Why embodied carbon must now be a priority

As the UK construction sector intensifies efforts to decarbonise, attention is rapidly shifting from operational emissions to embodied carbon — the emissions associated with material extraction, manufacturing, transport, and construction processes.

While operational energy is regulated through Part L and targeted by EPC ratings, embodied carbon remains largely unregulated in England. However, a landmark study commissioned by the Department for Levelling Up, Housing and Communities (DLUHC) and led by AECOM has brought this issue to the forefront. Their July 2025 report, The Practical, Technical and Economic Impacts of Measuring and Reducing Embodied Carbon in New Buildings, provides a roadmap for reducing embodied carbon through consistent practices, better data, and cross-industry collaboration.

The message is clear: if the UK is to meet its 2050 Net Zero commitment under the Climate Change Act, embodied carbon can no longer be treated as optional.

Key findings of the report

1. Technical gaps are undermining progress

Inconsistency in carbon assessments

AECOM identifies a fundamental challenge: a lack of consistency across carbon assessment outputs. Without a unified assessment methodology, results vary by tool, making cross-project comparisons and benchmarking unreliable.

Recommendations:

• Develop a nationally recognised reporting structure aligned with BS EN 15978 and BS EN 17472.
• Require every carbon assessment to disclose:
  
  • Building type
  • Element category scope
  • Lifecycle module coverage

This would create a level playing field and enable credible benchmarking, essential for future regulation and procurement criteria.

Data Gaps: EPDs and generic values

The report finds that one-third of sampled materials lacked a UK-specific environmental product declaration (EPD). This is particularly acute in categories like External Works and Building Services.

Recommendations:

• Establish a central UK carbon dataset that aggregates existing EPDs and verified generic values.
• Encourage wider EPD adoption through support programmes for manufacturers.
• Where data is lacking, promote interim methodologies such as CIBSE TM65, which estimates embodied carbon for building services components.

“Improving data quality for building materials is vital… A tiered data tracking approach will support the UK’s decarbonisation goals.”
— AECOM, 2025

Tool verification and industry trust

Without oversight, variations between carbon tools can be exploited — whether intentionally or not. This risks undermining the integrity of carbon reporting and discourages tool improvement.

Recommendations:

• Implement third-party verification for all carbon assessment tools.
• Verify key parameters such as:
  • Data sources
  • Scope of life-cycle modules
  • Modelling assumptions
  • Output formats

This will prevent greenwashing and promote the development of credible tools.

2. Practical barriers must be removed

Limited use of low-carbon products

The report highlights that emerging low-carbon materials, such as cross-laminated timber (CLT), face multiple barriers: cost, fire risk perceptions, and insurance hurdles.

Recommendations:

• Government-backed support to reduce the cost of producing EPDs and improve access to product-level data.
• Develop an Insurance Playbook (building on the Mass Timber Insurance Playbook) to support the uptake of innovative materials.
• Mandate fire performance disclosure of all materials, supported by specialist input.

A skills gap across the value chain

UK engineering codes — such as Eurocode 5 — are not yet adapted to modern materials like mass timber. This slows uptake and increases project risk.

Recommendations:

• Fast-track training once the new Eurocode 5 is released.
• Expand upskilling efforts beyond designers to include contractors, manufacturers, and fire engineers.
• Define professional competencies that include carbon modelling and whole-life design.

3. The economics of carbon assessment: Cost or opportunity?

Cost of assessment

The report outlines a range of costs depending on the project stage and scope:

While these may seem significant, AECOM compares them against the social cost of carbon, which is estimated by HM Treasury at £269 per tonne CO₂e (Green Book Toolkit). In many cases, the potential carbon savings outweigh the upfront analysis costs.

Catalysing the green economy

Embodied carbon assessments also have economic co-benefits. They:

• Support green jobs, including a new category of qualified carbon assessors.
• Stimulate demand for low-carbon products and services.
• Encourage process innovations that lead to long-term savings.

Currently, the UK has an estimated 80–330 trained carbon assessors. This is sufficient for low and medium demand, but would need to scale significantly under future regulation.

Recommendations:

• Define and track the number of competent assessors and establish a recognised training pathway.
• Partner with industry and educators to offer funded training that helps existing professionals become carbon assessors.

4. From theory to action: What the industry can do now

For architects and engineers

• Adopt verified carbon assessment tools that align with UK and European standards.
• Choose low-carbon design strategies such as:
  • Reused steel in lieu of virgin steel
  • Exposed ceiling instead of suspended ceiling
  • Pad foundations over piles, where feasible

For manufacturers

• Develop environmental product declarations (EPDs) to support procurement decisions and win specification opportunities.
• Join or initiate industry-led databases to improve data transparency.

For contractors and developers

• Embed embodied carbon assessments at RIBA Stage 2–3.
• Insist on carbon reporting as part of procurement contracts.
• Upskill in material selection and lifecycle thinking.
  
  

Frequently Asked Questions (FAQ)

What is the UK Government’s stance on embodied carbon?

While operational energy is regulated, embodied carbon remains unregulated in England. However, government-commissioned studies such as AECOM’s 2025 report signal a strong policy direction toward future regulation.

What standards should I follow?

BS EN 15978, BS EN 17472 and CIBSE TM65 are core references. Use tools aligned with these standards to future-proof your reporting.

Can carbon assessments save money?

Yes. Many carbon reduction strategies — like material optimisation or reuse — also reduce costs. The initial assessment fee can unlock significant lifecycle savings.

What support exists for SMEs?

Tools such as Carbon Designer 3D and the Future Homes Hub’s free tool offer accessible entry points for early-stage carbon analysis.

How One Click LCA can help reduce carbon

One Click LCA is uniquely positioned to help the UK construction sector put the AECOM / MHCLG report’s recommendations into action. With access to the world’s largest construction carbon database — featuring over 300,000+ verified data points, the platform enables consistent, accurate, and up-to-date embodied carbon assessments across all building types and life-cycle stages. Whether you’re an architect working at concept design, a manufacturer generating EPDs, or a consultant conducting whole-life carbon analysis, One Click LCA’s suite of tools, including Carbon Designer 3D, EPD Generator, and integrations with BIM and other design software, supports robust, standardised reporting aligned with BS EN 15978, BS EN 17472 and CIBSE TM65. Our tools help bridge critical data gaps, reduce the risk of misreporting, and ensure assessments are comparable, credible, and ready for third-party verification — making it easier to meet both current voluntary frameworks and prepare for future regulatory requirements. For SMEs and larger firms alike, One Click LCA accelerates the ability to design, procure and build for net zero.